You've got to give it to Cadillac. With the 2008 STS, the company has increased the power output of its V6 engine by 47 horsepower and also increased the car's overall shininess by 103 percent.
Since the introduction of the current-generation STS in 2005, this middle-of-the-road sedan has been the overlooked middle child of the Caddy lineup. It's never been the athlete that the smaller CTS has been. Nor has it been anywhere near as accommodating or successful as its big brother, the DTS.
So it is with just a smidge of guilt that we reveal here that our greatest interest in this reworked STS lies in its new 302-hp, direct-injection 3.6-liter V6 and six-speed automatic transmission. This combination will be the uplevel powertrain for the fully redesigned 2008 CTS sedan, a car that has the panache that even this revised 2008 Cadillac STS still lacks.
Sapele Pommele, Sapele Pommele, etc.
The interior's new Sapele Pommele wood trim not only looks like genuine wood fiber, but its name also rhymes with itself, so it's as enjoyable to pronounce as it is to see as you look around the new, less dour interior. Can't say that about walnut, can you?
We also like the handsome new three-spoke steering wheel with satin metal spokes and a rim inlaid with Sapele Pommele. We like the new satin metal trim that sets off the Sapele Pommele on the center stack. We like the new instrument panel gauges, and while they are not quite "chronograph-like" as Cadillac claims, they are cheery and considerably less cheap-looking than the dials they replace. Also they are mounted quite close to several more chunks of Sapele Pommele wood veneer. Why this kind of warm, luxurious detailing hasn't been a part of the current-generation STS since its introduction in 2005 is beyond us.
Likewise we generally like the changes that have been made to the exterior of the '08 STS. Particularly nice is the big grille, which has dark egg-crate grilles within each segment of the bright and shiny egg-crate grille. If you're having trouble visualizing this, go have a look at your nearest Escalade. It's much more handsome than it sounds and gives the STS nose some character in place of the insipid look of the previous front end.
We suspect Cadillac was reluctant to provide too much luxury adornment for the 2005 STS for fear it might be dismissed as something less than the serious German-style sedan it aspired to be. But we have no problem with chrome. It's shiny. And like the largemouth bass and fans of Las Vegas, we like shiny things. Every 2008 STS gets this king-of-trim material on each of its four door handles, the rocker panels and the dinky fender vents.
Go Direct to 302 Horsepower
The 302-hp, 3.6-liter direct-injection V6 makes more peak horsepower than BMW's new twin-turbocharged 3.0-liter inline-6. OK, the Cadillac V6 only makes two more horses than the premium Munich motor, but it also makes a whopping 72 hp more than the normally aspirated 3.0-liter inline-6 with which the base-model 5 Series is equipped. The Cadillac V6 also has the Mercedes-Benz E350's 3.5-liter V6 covered.
Cadillac reckons 302 hp and the new standard six-speed automatic transmission is enough to get the V6-powered STS to 60 mph from a standstill in 6.5 seconds, 0.6 second quicker than the former combination of 255-hp, 3.6-liter V6 and five-speed automatic. Shooting fuel directly into the combustion chamber provides a cooler intake charge, which permits an increase in compression ratio from 10.2:1 to 11.3:1. More compression ratio plus improved flow of intake air means more power.
Direct injection also provides better fuel economy than a conventional fuel-injection system. Cadillac estimates a 3 percent reduction in fuel consumption. There's also a 25 percent reduction in cold-start hydrocarbon emissions.
So let's review. Lower emissions. Higher fuel-efficiency. And much great power. Nothing wrong with that.
And, indeed, the engine is impressive. It doesn't feel quite as powerful in the STS as its numbers suggest, but perhaps this is due to the car's weight and the six-speed transmission's reluctance to downshift. And Caddy's V6 also transmits some vibration through the accelerator pedal and steering wheel and even sounds a bit strained at very high engine speeds.
Incidentally, the 320-hp Northstar V8 naturally is still available for the 2008 Cadillac STS.
Electrons Are Taking Over
Other changes to the 2008 STS reflect Cadillac's decision to use this car as a showcase of new technology. For this car, there are three such new technologies, all of which are related to safety.
Most significant is the integration of the variable-ratio steering arrangement with the stability control system. Much like BMW's active steering, the Cadillac system varies the steering effect according to speed, so the same amount of angle on the steering wheel delivers a steering ratio of 12:1 at low speeds and a 20:1 steering ratio at high speeds. The goal is to reduce the amount of steering wheel spinning required around town but without any sacrifice in the impression of high-speed stability.
Integrated as it is with the stability control system, the steering can also automatically provide a little countersteer should the rear of the car get loose for some reason. It sounds a little creepy in theory, as if the electrons were taking command of the car, but we found it pretty effective. The active steering system is available only for the V8-powered, all-wheel-drive STS.
The excellent Magnetic Ride Control dampers are available on V8 cars only. The new-for-2008 performance handling package — including 18-inch chrome-plated wheels, Brembo brakes with four-piston calipers and wider Michelin Pilot Sport summer tires — is offered on the V8-powered STS in either standard rear-wheel drive or optional all-wheel drive. Meanwhile, the handling package is available for the rear-drive V6 STS but not on the all-wheel-drive V6 STS. Ordering an STS with the exact combination of attributes and technologies you'd prefer might be like playing bingo with the check-off boxes on the order sheet.
Blind Me With Science
Every 2008 STS can be had with Cadillac's new and annoying Lane Departure Warning system. Like similar systems already on the market, Cadillac's Lane Departure Warning system uses a camera housed in a conspicuously large black plastic box beside the rearview mirror to detect the lane markers on the road in front of the car.
Once you drift too close to a lane marker, the system beeps three times and flashes a yellow icon on the instrument panel. It would seem the only people to benefit from such a system are exactly those people who shouldn't be on the road in the first place, such as the sleepy, the drunk or the terminally uncoordinated.
Cadillac will also wire up your STS to detect vehicles in the blind spots around its rear flanks. A little icon flashes on the outside mirror if someone is hanging out in your no-vision zone.
The Bottom Line on the Middle Line
The 2008 Cadillac STS goes on sale in July of this year for what we estimate to be a modest increase in price over the '07 model. It is more handsome, more distinctive and certainly more powerful than the model it updates. All this makes the STS a better car.
Yet the brawny, substantially new CTS arrives only about a month or two later than the STS, and this will steal what little crackle of thunder the bigger car generates. So we anticipate that the DTS will remain the best-selling Cadillac sedan for at least a couple of years. This leaves the 2008 Cadillac STS in its familiar role as the overlooked middle child.
The manufacturer provided Edmunds this vehicle for the purposes of evaluation.